Varicella-Zoster Virus Epithelial Keratitis in Herpes Zoster Ophthalmicus

Transcription

1 Varicella-Zoster Virus Epithelial Keratitis in Herpes Zoster Ophthalmicus

2 Helena M. Tabery Varicella-Zoster Virus Epithelial Keratitis in Herpes Zoster Ophthalmicus In Vivo Morphology in the Human Cornea

3 Helena M. Tabery Ögonkliniken UMAS Malmö Sweden ISBN e-isbn DOI / Springer Heidelberg Dordrecht London New York Springer-Verlag Berlin Heidelberg 2011 This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product liability: The publishers cannot guarantee the accuracy of any information about dosage and application contained in this book. In every individual case the user must check such information by consulting the relevant literature. Cover design: estudiocalamar, Figueres/Berlin Printed on acid-free paper Springer is part of Springer Science+Business Media (

4 Preface This book treats varicella-zoster virus (VZV) caused corneal epithelial changes captured in high-magnification photographs in herpes zoster ophthalmicus (HZO). The images highlight the typical substructure of VZV lesions clinically presenting in a large variety of shapes and sizes, both in conjunction with and in the absence of typical HZO rash; the accompanying case reports illustrate the varying clinical features of the disease, ranging between typical and rare ones. In addition, the book shows serial photographs capturing the dynamic features of VZV impact on the corneal epithelial architecture. The opportunity was unique, not only because the corneal epithelium is the only one in the human body in which morphological changes can be directly observed and followed without intervention, and highlighted by in vivo staining, but also because the follow-up was not terminated by treatment. Contrary to expectations, the at that time recommended antiviral drug (acyclovir or valacyclovir) showed no detectable effect, neither on the morphology nor on the dynamics of the epithelial disease. In the interpretation of the disturbances of the epithelial architecture, this book partly relates to the morphology of herpes simplex virus (HSV) caused changes, for reasons extending beyond differential diagnostics. The point is that it is not only the impact of the infection that has to be taken in account, but also epithelial healing responses. When the similarities between the two viruses are sorted out, very different reparative patterns emerge; these patterns indicate that after having reached the corneal epithelium via the same route, the two viruses strongly diverge in their behaviour. Because all this is reflected in the individual lesions, the comparison between them can explain at least some mechanisms behind their appearance. With this book I intended to fill a void in the literature by adding high-magnification in vivo images that capture several aspects of an intriguing disease so far defying attempts to be reproduced in laboratory animals. I hope I have done that. Malmö, Sweden January 2010 Helena M. Tabery v

5 Contents 1 2 The Morphology of Varicella-Zoster Virus Epithelial Keratitis in Herpes Zoster Ophthalmicus VZV Cytopathic Effect in Cell Cultures VZV Cytopathic Effect in the Living Human Corneal Epithelium VZV Epithelial Keratitis: Surface Elevations and Disruptions VZV Epithelial Keratitis: Dynamics of Fluorescein Sodium Staining..... VZV Epithelial Keratitis: Surface Plaques VZV Epithelial Keratitis and Epithelial Edema Epithelial Erosion: A Sequela of VZV Epithelial Keratitis Subepithelial Opacity: A Sequela of VZV Epithelial Keratitis (1) Subepithelial Opacity: A Sequela of VZV Epithelial Keratitis (2) Inflammatory Cells on the Endothelium in VZV Epithelial Keratitis (1)... Inflammatory Cells on the Endothelium in VZV Epithelial Keratitis (2) The Dynamics of Varicella-Zoster Virus Epithelial Keratitis in Herpes Zoster Ophthalmicus Case 1: Changing Shapes of a Large VZV Lesion Case 2: Changing Shapes of a Smaller VZV Lesion Case 3: Appearance and Disappearance of VZV Corneal Epithelial Lesions Development of VZV Corneal Epithelial Lesions in the Same Location Recurrent VZV Epithelial Keratitis in HZO; HZO Sine Herpete Case 1: Recurrent VZV Epithelial Keratitis in HZO Case 2: Recurrent VZV Epithelial Keratitis in HZO Case 3: Recurrent VZV Epithelial Keratitis in HZO Case 1: VZV Epithelial Keratitis in HZO Sine Herpete Case 2: VZV Epithelial Keratitis in HZO Sine Herpete Case 3: VZV Epithelial Keratitis in HZO Sine Herpete vii

6 viii 4 Contents Three Rare Cases of Ocular Surface Involvement in Acute HZO Case 1: H ZO, Epithelial Edema, and (Presumed) VZV Epithelial Keratitis Case 2: HZO and Corneal Epithelial Cysts Case 3: HZO, VZV Epithelial Keratitis, and VZV Conjunctival Lesions Comparison of HSV and VZV Epithelial Keratitis Swollen Epithelial Cells; Surface Ulceration (HSV) Subsurface Changes, Surface Elevations Light-Reflecting Properties Light-Reflecting Properties and Staining Features Various Aspects of an HSV Lesion Various Aspects of a VZV Lesion The Origin of HSV Dendrites and VZV Pseudodendrites Fluorescein Staining of HSV Dendrites and VZV Pseudodendrites Rose Bengal Staining of HSV Dendrites and VZV Pseudodendrites Addendum. Interplay of Destructive and Healing Forces in HSV Epithelial Keratitis Final Remark Bibliography Index

7 About Herpes Zoster Ophthalmicus Infection with varicella-zoster virus (VZV) causes varicella (chickenpox), a disease that manifests as a disseminated vesicular body rash. After that, the virus remains latent in the sensory ganglia; it reactivates later on and causes new symptoms herpes zoster (HZ). In herpes zoster ophthalmicus (HZO), the reactivated virus descends from the trigeminal ganglion through the first division of the fifth nerve, the nervus ophthalmicus, which via its different branches supplies the skin of the forehead, the lids, the nose, and the eye. HZO is a very common disease affecting the elderly; it is rare in children and young adults. At all ages, immunosuppression is a predisposing factor. HZO might severely damage any eye structure and even result in a destruction of the eye. The HZO diagnosis is clinical. It is easy in patients presenting with a typical vesicular rash, challenging when mimicked by vesicles caused by herpes simplex virus (HSV), and may be missed when skin eruptions are lacking (zoster sine herpete). The problem is that almost all HZO ocular manifestations are per se unspecific and often indistinguishable from those occurring for other causes in general and those caused by HSV infections in particular. Yet, there is one exception VZV epithelial keratitis. Clinically, it is the least troublesome of VZV ocular manifestations, but it occupies an outstanding position because of its typical features. VZV epithelial keratitis may precede the rash, accompany it, develop later on, and recur; in some patients, it may be the only clue revealing the true cause of their disease. ix

8 About This Book The photographs presented in this book have been chosen to show The in vivo morphology of VZV corneal epithelial lesions in patients with HZO, accompanying signs and sequelae (Chap. 1) The dynamic features of VZV corneal epithelial lesions in patients with HZO (Chap. 2) The morphological and dynamic features of VZV epithelial lesions in HZO sine herpete and of recurrent VZV epithelial lesions (Chap. 3) Three rare cases of ocular surface involvement in HZO (Chap. 4) A comparison of (HZO) VZV and (recurrent) HSV corneal epithelial lesions (Chap. 5) The photographs were taken by non-contact in vivo photomicrography, a method that requires neither contact with the epithelium nor the use of anesthetics. By this method structures that optically differ from their regularly organized surroundings are visualized; a normal corneal epithelium or stromal cells cannot be discerned. As there is no contact with the ocular surface, the architecture of epithelial changes is not disturbed by the examination, and there is no risk of spreading infections. The technique allows the use of various illumination modes to complement each other and a free application of diagnostic dyes to expand the information, e.g., 1% fluorescein sodium and 1% rose bengal (preservative-free solutions). These dyes are commonly used in clinical practice. The diagnosis was clinical; in some cases, it was verified by PCR. The photographs of cell cultures were taken by the same method. The bars indicate 200 mm throughout the book. xi

9 Abbreviations CPE Fluorescein IOP HIV HSV HZO KCS PCR VZV Cytopathic effect Fluorescein sodium Intraocular pressure Human immunodeficiency virus Herpes simplex virus Herpes zoster ophthalmicus Keratoconjunctivitis sicca Polymerase chain reaction Varicella-zoster virus xiii